Applicability of Rice Husk Residue Generated by the Silica Extraction Process to Anaerobic Digestion for Methane Production

Rice husks are a feedstock of biogenic silica because their high content. After extraction, solid residue comprising mostly carbohydrates is present. Solid valorization important for closed-loop systems using rice husk and has minimal negative environmental impacts. In this study, we used that was generated by extractionto anaerobic digestion producing biomethane. The characterized in terms total solids, volatile pH, composition, particle size. Changing the characteristics increased biogas production 2.48-fold compared to raw husk. produced 166.4 mL-biogas g−1 vs. 100.4 mL CH 4 VS, much more than previously reported. Microbial community analysis, which conducted investigate biological reasons methane, found Bacteroidetes levels samples. Among archaeal communities, Bathyarchaeota abundant all samples inoculum. contained operational taxonomic units other These changes microbial significantly influenced improved methane production. Our findings provide basis cleaner utilization produce renewable energy.